document.write( "Question 139052: Stanbon here are the other two that I needed to repost. I know it gets late there as I'm in another country, thanks for all of your help, your the best.\r
\n" ); document.write( "\n" ); document.write( "1. In Utica, Michigan, 205 of 226 school buses passed the annual safety inspection. In Detroit, Michigan, only 151 of 296 buses passed the inspection.
\n" ); document.write( "(a) State the hypotheses for a right-tailed test.
\n" ); document.write( "(b) Obtain a test statistic and p-value. (c) Is normality assured? (d) If significant, is the difference also large enough to be important? \r
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\n" ); document.write( "\n" ); document.write( "2. Prof. Green’s multiple-choice exam had 50 questions with the distribution of correct answers shown below. Research question: At α = .05, can you reject the hypothesis that Green’s exam answers came from a uniform population\r
\n" ); document.write( "\n" ); document.write( "Correct Answer Frequency
\n" ); document.write( "A 8
\n" ); document.write( "B 8
\n" ); document.write( "C 9
\n" ); document.write( "D 11
\n" ); document.write( "E 14
\n" ); document.write( "Total 50
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Algebra.Com's Answer #101437 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
I answered those this morning at 7:00 EST.
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\n" ); document.write( "2. In Utica, Michigan, 205 of 226 school buses passed the annual safety inspection. In Detroit, Michigan, only 151 of 296 buses passed the inspection.
\n" ); document.write( "(a) State the hypotheses for a right-tailed test.
\n" ); document.write( "Ho: p(Ut)-p(Dt)= 0
\n" ); document.write( "Ha: p(Ut)-p(Dt)>0
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\n" ); document.write( "(b) Obtain a test statistic and p-value.
\n" ); document.write( "p-hat(Ut) = 205/226= 0.9071;p-hat(Dt)=0.5101; p(pooled)=(431/522)=0.8257
\n" ); document.write( "z = (9071-0.5101)/[ 0.8257*0.1743/226 + 0.8257*0.1743/296]= 9.6491
\n" ); document.write( "p-value: 2.52x10^-22
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\n" ); document.write( "(c) Is normality assured?
\n" ); document.write( "I'll let you check out those conditions.
\n" ); document.write( "They should be listed in your text.
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\n" ); document.write( "(d) If significant, is the difference also large enough to be important?
\n" ); document.write( "Since p-value is so small the difference is very significant.
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\n" ); document.write( "3. Prof. Green’s multiple-choice exam had 50 questions with the distribution of correct answers shown below. Research question: At α = .05, can you reject the hypothesis that Green’s exam answers came from a uniform population
\n" ); document.write( "Correct Answer Frequency.......Expected
\n" ); document.write( "A ................8................10
\n" ); document.write( "B ................8................10
\n" ); document.write( "C ................9................10
\n" ); document.write( "D ...............11................10
\n" ); document.write( "E ...............14................10
\n" ); document.write( "Total 50
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\n" ); document.write( "Ho: Observed Frequencies are equal
\n" ); document.write( "Ha; Observed Frequencies are not equal
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\n" ); document.write( "I ran a Chi-Sq Test on a 2x5 matrix with observed in the 1st row and expected in the 2nd row and got the following results:
\n" ); document.write( "Test statistic: Chi-Sq = 1.2114
\n" ); document.write( "p-value: 0.8762
\n" ); document.write( "Meaning: 87.6% of test results could have given stronger evidence for
\n" ); document.write( "rejecting Ho.
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\n" ); document.write( "Conclusion: Since p-value is greater than alpha=5%, Fail to reject Ho.
\n" ); document.write( "The grades follow a uniform distribution.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \r
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